Kelly bar is the key part of a drilling machine, and its quality directly affects the performance of the whole machine. The main purpose of kelly bar is to transfer the torque of rotary drive and crowd pressure of the crowd system to the drilling tool. Based on the rich manufacturing experience and by absorbing the advanced technology both at home and abroad, we can produce first-class kelly bar which can be compared favorably with the imported ones.
The features of UNIMATE kelly bar are as follows:
Adopt the advanced technology of 6-key design in the world and standard modular design.

Equipped with advanced processing facilities, workmanship and manufacturing equipments, UNIMATE kelly bar enjoys a low weight, high strength, high straightness of single bar, thinner tube, smaller inter-tube distance and good abrasion resistance.

The raw materials are either imported from Germany like the high abrasion resistance materials, or from Chinese top manufacturer such as the seamless steel tube with alloy. All the tubes made in China are specially made seamless alloy tube, which guarantees the accuracy of the sizes, location, physical properties and easy welding. The small-diameter tubes undergo reheat treatment. The friction kelly bar can be used under full torque.

All the outer keys have undergone special heat treatment; therefore, they possess higher hardness, higher flexibility and excellent welding properties, which provide higher abrasion resistance to the keys.

There are mainly two types of Kelly bars:
1- Interlocking Kelly Bar
2- Friction Kelly Bar